CNC 工具機加工精度與節能同步優化智能設計

Intelligent optimization system of machining accuracy and energy efficiency for CNC machine tool

陳楚河(Tsooj Shambaljamts)

指導教授 ： 王世明

中原大學/工學院/機械工程研究所/博士(2017年)

https://doi.org/10.6840/cycu201700666

摘要

所提出的研究包括相關部分。 第一部分討論使用經驗/實驗的概況建模銑削能耗模型，並研究在某些材料去除率下切削參數對能耗及表面粗糙度的影響和優化。
一般廠商最常用的三軸CNC工具機其主要耗電馬達包含一個主軸馬達和三個伺服軸馬達，其他如冷卻液泵、自動換刀馬達、排屑馬達或液壓系統因相對功率或使用時間較低，因此其對機台總體耗電的影響也較輕。若欲分析機台加工條件與耗電量之間的關係，可以分析主軸馬達和伺服軸馬達為主。在同步考慮機台耗電與加工精度下，應該根據馬達耗電特性選擇最佳的切削參數組合，求得加工精度與耗電的優化組合。該功耗模型旨在最佳能源效率、成本和加工時間，並以C＃語言軟體建人機介面。根據實驗結果，觀察到銑削過程的能量需求顯著依賴於主軸與進給運動之間的相互作用以及切削參數和材料去除速率的選擇。
材料去除率（MRR）是主軸能耗影響最大的因素。 切深、切寬及進給也顯著影響能耗。 另外，使用實驗數據及統計建模獲得模型係數的值，將易於被理解與解釋能耗模型。 用材料去除率相同，優化的參數將降低能耗和綜合成本30.1％和32.5％。 從粗糙度測量得到的結果可以看出，在軸向和徑向切深的高比例下，表面粗糙度的最小Ra值發生在高速的主軸轉速。
第二部分研究集中在慣性效應和摩擦力對CNC工具機運動精度的影響。 在這項研究中極而可利用即時調整CNC控制參數的方法來做到對慣性校應的最佳控制。研究中使用Ball-Bar系統來了解和分析CNC工具機誤差及補償參數功能。 本研究開發機上工件重量變化辨識系統。 介紹正圓度誤差和誤差補償。 加工之前，可檢測到工件的重量，用於確定最佳加工加工參數與補償值。 最後，實驗與驗證結果顯表明，該系統可以通過補償和加工參數提高機器的精度。

關鍵字

CNC工具機 ； 產效 ； 節能 ； 優化 ； 慣性 ； 摩擦效應 ； 精度

並列摘要

The research that I present consists of inter-related parts. The first part discusses the outline of the empirical/experimental study of energy efficiency improvement for end milling processes and also it studies the optimization and the influence of process parameters on power consumption as well as surface roughness at certain material removal rate.
The main energy consuming components of 3-axis CNC machine tools were the spindle, three axis servos, a coolant pump, a tool change system, a chip removal system, and the hydraulics. However, the tool change system, the chip removal system, and coolant are not significantly influenced in total material cutting energy consumption due to not frequently used for cutting process. The material cutting power is mainly consumed by the spindle and servos. Furthermore, the spindle and three axes servos were considered as the energy consumption model to reduce power consumption by synchronizing the spindle and axis movement. In order to evaluate the energy efficiency and a machining accuracy, system for the energy monitoring and a process optimization was developed based on the spindle and axis feeding power consumption model. This power consumption model is designed to maximize the energy efficiency and minimize a processing cost and time, and to solve problems via user-friendly interface, written by Visual C# software. A new set of parameters has been defined to validate the proposed system.
The second part of the research is focused on influence of an inertial effect and a friction force on the CNC machine tools’ servos accuracy. In this study, a ball-bar system was used to understand and analyze the characteristics of a control parameters function of a CNC controller. By using empirical method, an adaptive tuning system that can tune the CNC control parameters on the detected weight of workpiece was developed. During machining process, the weight of the machined workpiece was detected which was used for determining the optimal control parameters that could fit the current machining status. Finally, the results of several experiments, which were conducted to verify the proposed functions, have shown that the system can effectively improve the accuracy of a machine tool through adaptive tuning control parameters based on the current weight of the machined.

並列關鍵字

CNC machine tools ； energy consumption ； optimization ； inertial effect ； accuracy ； adaptive tuning ； weight monitoring

參考文獻

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